Knife guard for slicing machines



Nov. 6, 195] D, MEEKER ET AL 2,573,860

KNIFE GUARD FOR SLICING MACHINES Original Filed Dec. 20, 1946 2 SHEETS'SHEET l r WW Hum ""WW INVENTOIRS AT TORN E Y8 N v- 6, 1 D. A. MEEKER Em "2 73, 60

KNIFE GUARD FOR SLICING MACHINES Original Filed DQC. 20, 1946 2 SI-IEETSSHEET 2 44 v 71 I 58 45 75 57 4e ATTORNEYS Patented Nov. 6, 1951 KNIFE GUARD FOR SLICING MACHINES David A. Meeker, Troy, and Ernest A. Reussenzehn, Dayton, Ohio, assignors to The Hobart Manufacturing Company, Troy, Ohio, a corporation of Ohio Original application December 20, 1946, Serial No. 717,566. Divided and this application August 28, 1948, Serial No. 46,614

3 Claims. (Cl. 146-402) This invention relates to slicing machines, and is a division of parent application Serial No. 717,566, filed December 20, 1946.

It is the principal object of the invention to provide a slicing machine of the gravity feed type which is simple and economical in construction and which isso arranged that with a minimum of effort the entire machine can be maintained in a clean and sanitary condition.

It is also an object of theinvention to provide such a machine which is constructed with a minimum number of parts which can be easily and cheaply manufactured and assembled, and in which the parts exposed to the foodstuff may be given a smooth surface finish facilitating the maintenance of the entire machine in a clean and sanitary condition.

It is a further object to provide a simple and satisfactory construction of knife guard plate which does not interfere with the normal feeding of the work material during use and which may readily be removed for cleaning and the like.

Other objects and advantages will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings:

Fig. 1 is a plan view of a gravity feed slicing machine constructed in accordance with the present invention;

Fig. 2 is a partial vertical sectional view on the line 2-- 2 of Fig. 1 showing the knife and its supporting and driving mechanism;

Fig. 3 is a small sub-assembly view of the knife and knife guards to show the location of the notches that receive the lugs on the knife plate; and

Fig. 4 is a sectional view showing a detail of the mechanism for securing the knife plate in place.

Referring to the drawings, which disclose a preferred embodiment of the invention, the ma chine comprises a main base member ID which extends across the entire lower portionof the machine, serving as a base and main supporting frame. Prefer-ably this member is made of a relatively lightweight material such as a suitable aluminum-containing alloy so as to reduce the overall weight and keep the machine readily portable. If desired the outer exposed surface may be suitably finished to provide a smooth surface which can be readily kept in a clean and sanitary condition, such surface being either painted or preferably anodically treated. The base carries mountings for rubber cushion members II which may be located at the four corners to provide for resiliently supporting the entire machine'in non-slipping engagement and with the lower edge of the main frame raised slightly above the supporting surface.

At one side the frame member i8 is formed with a generally rectangular opening I? having a surrounding rim |3 which is relatively fiat on top and thus is adapted to receive a slice tray l5. Preferably the frame member is grooved as indicated at I6 and Il, the grooves extending at right angles to each other along one side and end providing for the edge of the tray being slidably received and locked in position in the groove so formed. The tray is retained in the groove by a single screw l8 which is located in the outer corner of the frame and is accessible from the lower side of the frame. Tray I5 may suitably be formed as either a molded metal, stamping or plastic element, the surface of which is smooth and easy to maintain in a clean and sanitary condition, and aswill be evident from the drawings it extends over a substantial part of the length and width of the base, entirely underlying the gage plate 2i! and the cutting portion of the knife 22.

The base is formed with an integral upwardly extending part 25 at the rear side thereof, and within this portion there is received the drive motor, the end cap. of which is shown at 25. The motor thus stands with its drive shaft substantially horizontal. On the forward side, the main frame is provided with an integral upwardly extending curved part 2! which extends along the front face of the machine with a vertically extending wall portion 28 on the forward side, this curved portion 21 forming an enclosed cover construction for the supporting mounting of the carriage, the latter being shown as comprising two plate portions, a near plate 30 toward the operators end of the machine and a far plate 3| away from the operators position in the forward direction of travel of the carriage during the cutting stroke, these two plates being arranged and mounted at right angles to each other. gage plate 20 is mounted in side-by-side relation with the knife 22 and at such an angle that it is substantially parallel with the plane of the knife, both of these elements being supported with their planes substantially normally to the downwardly inclined path of travel of the work material moving through the carriage.

Between the rearward portion 25 and the forward portion 21, the frame is formed with an integral curved part or collecting trough 33 which has a definite slope from the rear of the machine downwardly toward the slice tray l5. As

The

shown in Fig. 2 the trough 33 extends forwardly beyond the lower edge of the knife 22 and fully underlies the entire cutting arc of the knife and the adjacent portion of the gage plate 28 where scraps are most likely to fall. Such scraps are received in the trough and either discharged downwardly onto the slice tray, or they are collected in a location from which they may be easily removed by the operator who has ready access to this portion of the machine because of the substantial radius of curvature of the portion 33 and the freedom of access from both ends thereof. The frame thus affords a continuous closed construction extending in impervious sealed relationship throughout the entire base of the machine, preventing downward passage of scraps of food material to the space below the frame and facilitating the collection and discharge of all such material in a location from which it can be easily removed by a simple wiping operation.

The motor shaft is shown at 35 extending into the raised portion of the frame and having secured thereon the drive worm which meshes with a worm gear 3? keyed by means of key 38 to a knife shaft 48. A look nut 4| kept tight by screw 42 provides for detachably securing the worm gear 37 in position on the shaft. The knife shaft is journaled in ball bearings 43 and 44 respectively which are supported in a sleeve member 45 supported in the rear frame element 20. Bolts 45 provide for removably securing the sleeve in position. As shown in Fi 2 the shaft is supported at an angle to the horizontal of about 45, such that it will provide for the proper driving and support of the rotary knife in the desired plane.

The knife 22 is formed with a recessed face and is suitably secured to the knife shaft 58 by means of a series of bolts 5!, the knife being centered on the projecting end 52 of the knife shaft. Suitable sealing elements 53 prevent escape of lubricant outwardly onto the knife surface. A center abutment pin 54 of fiber or the like is adjustably threaded into the end of the knife shaft to form a support for the knife guard plate and seats against an inner threaded pin 55 of steel. The inner pin is first positioned in proper location and then the outer pin seated against it, the rotation of the knife keeping the outer pin tight against the inner pin.

Sleeve 45 is provided with a flanged portion 56 and with a peripherally grooved portion 57 which is adapted to receive the locking flange 58 of a pair of knife guard members comprising lower member 68 and upper member Bl. The two knife guard members 68 and GI each cover approximately half of the knife periphery, and they are adapted to be inserted and removed in a predetermined order of sequence. Thus the flange 58 of the knife guard member 60 is provided with an inwardly extending lug 62 (Fig. 3) which passes through a slot 63 in flange 56, and upon the subsequent turning of the knife guard member 60 about the axis of the shaft 48, locking lug 52 will engage and lock into the groove B l in the flange 56 to prevent direct withdrawal of the guard member while allowing it to rotate around to its final operative position where it engages a stop pin.

After the lower guard member 68 has been so positioned and locked in place the upper guard member 6| is moved downwardly into position without rotation, this member carrying a lug 65 having a tapered opening 66 therein which is adapted to align with a pin 61, carried as shown in Fig. 2 in frame member 25. Pin 61 is yieldably urged toward locking position by means of spring 68, but may be manually withdrawn through the operation of a button 18 attached to the end of the pin and accessible on the outside of the frame.

When the upper guard member 6| is to be positioned in operative position it may be pressed downwardly and pin 61 will snap into position to retain both guard members in locked position. The end of the pin 61 is tapered and thus a firm locking engagement is established when the tapered pin engages the correspondingly tapered opening 66. Preferably the lower end H of the lug 65 is likewise tapered so that as the guard is moved downwardly into operative position the tapered end H contacts the tapered pin 61 to cam the pin backwardly and thus facilitate the establishment of the proper locking relation. In order to remove the guard it is necessary for the operator manually to move button 10, withdrawing pin 61 from engagement in slot 66. No manual operation, however, is required to lock the guard in place, and the guard can thus be assembled by a simple movement of one hand. Cross reference is made to Patent No. 2,412,962, assigned to the same assignee as this application, which shows certain of the features described above.

In order to protect the front face of the knife and to provide support for the work material after the same is reciprocated across the knife face, a knife guard member or knife plate 15 is provided which as shown in Fig. l overlies the greater part of the front face of the knife, leaving only the cutting edge thereof exposed. Preferably the knife guard is likewise recessed as shown at 7'! to fit within the recessed face of the knife and provide a smooth supportin surface for the work material as it moves across the face of the knife.

The knife plate 15 is supported from the knife guard 686I through the provision of a plurality of spaced arcuate recesses and 8| (Fig. 3) in the lower knife guard 58 within the peripheral rib 82 on the front face thereof. Similar recesses 83 and 84 are formed in the same relative positions in the rib portion 85 of the guard 6|, with the rib portions extending over the forward side of each of these recesses. Cooperating with such recesses are lugs 88, which are formed integrally with plate 15 and shaped to correspond with the recesses to thus lock the knife plate in properly supported operative position. A handle secured to the upper portion of the knife plate provides for convenient handling thereof.

In the assembly and removal of the knife plate 15, the lower guard member 60 is first placed in operative position as described above and knife plate 15 is then moved into operative position with its two lower lugs 88 engaging in the lower grooves 80 and 8!. The upper knife guard member 6| is then moved downwardly into operative position in the manner described above, this movement providing for the upper pair of lugs 88 being received in the upper grooves 83 and 84, where it is locked in place by the pin 61 as described to thus securely support the knife guard in operative position against the downward force applied by the work material moving in the carriage. The abutment 54 is suitably adjusted to support the plate from the center thereof to avoid deflection under load. It will also be clear that with this construction the knife guard amseo is prevented from movement either in the plane of the knife, normal thereto or with a rotary motion, and it is thus securely held in proper operative position while at the same time it may be readily removed for cleaning and as easily reassembled. As will be clear from Fig. 2, the lower guard 60 because of its angular mounting upon the inclined knife does not obstruct the scrap passage 33 but leaves it free and clear for application of a cleaning cloth in the hand of the operator.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A food slicing machine comprising a base, a rotary knife mounted on said base, a work receiving carriage mounted for reciprocating movement along said base, a removable knife guard for the exposed peripheral edge of said knife including a plurality of sections of segmental shape, each said section having thereon a peripheral rib overlying said knife edge, said knife guard having recesses in the radially inward side of said ribs forwardly of said knife with said ribs extending over the forward side of said recesses, a knife plate removable separately from said knife guard and adapted to overlie the major portion of the face of said knife to support the pressure of the work material in said carriage toward said knife, said knife plate having radially extended lugs on the periphery thereof receivable in said recesses respectively for firmly supporting said knife plate in protective position over the face of said knife against said pressure, and means for removably mounting said knife guard sections on said base for separate sequential removal and assembly thereof to effect relative engagement and disengagement of said lugs and said recesses by relative movement of said guard sections and said knife plate transversely of the axis of said knife.

2. A food slicing machine comprising a base, a rotary knife mounted on said base, a work receiving carriage mounted for reciprocating movement along said base, a removable knife guard for the exposed peripheral edge of said knife including upper and lower sections each having thereon a peripheral rib overlying said knife edge, a knife plate removable separately from said knife guard and adapted to overlie the major portion of the face of said knife to support the pressure of the work material in said carriage toward said knife, said knife plate having radially projecting lugs in the periphery thereof, said ribs on said knife guard sections having recesses therein open only in the radially inner surface thereof for receiving said lugs to support said knife plate in protective position over the face of said knife, means on said base for supporting said lower guard section with said recesses therein in position to receive said lugs on the lower edge of said knife plate, and means on said base for securing said upper guard section in cooperative relation with said lower section upon movement of said upper section transversely of the axis of said knife toward said knife plate and said lower guard section to effect engagement of said lugs on the upper edge of said knife plate in said recesses in said upper guard section.

3. A food slicing machine comprising a base, a rotary knife mounted on said base, a work reeeiving carriage mounted for reciprocating movement along said base, a removable knife guard for the exposed peripheral edge of said knife including a pair of separate segmental guard sections together covering substantially more than half the periphery of said knife and each having thereon a peripheral rib overlying and adapted to project beyond said knife edge, said knife guard segments having recesses in the rib portions thereof closed on the face of said ribs and opening radially thereof, a knife plate removable separately from said knife guard and proportioned to be received radially inwardly of said ribs on said knife guard to overlie the major portion of the face of said knife, said knife plate having peripheral portions slidably receivable in said respective recesses with said recessed rib portions overhanging said peripheral portions requiring assembly on said base of one of said guard sections and then said knife plate followed by the other said guard section in said sequence to accomplish interfitting of said portions, and means for releasably securing said guard sections in assembled position on said base with said interfitting portions cooperating to releasably support said plate at the periphery thereof against both axial and angular movement with respect to the axis of said knife.

DAVID A. MEEKER. ERNEST A. REUSSENZEHN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,945,269 Freudenberg Jan. 30, 1934 2,030,197 Campbell Feb. 11, 1936 2,052,366 Ahrndt et a1. Aug. 25, 1936 2,126,380 Folk Aug. 9, 1938 2,412,962 Brookhart Dec. 24, 1946 2,438,937 Metzler Apr. 6, 1948 

